(1)
Where an enclosed tower silo, horizontal silo, or grain storage bin is connected to an adjacent feed room, mechanical exhaust ventilation shall be provided to remove air from the lowest floor level of the feed room to the outdoors at a rate not less than 3 air changes per hour.
(2)
The ventilation system of the farm building in which the feed room referred to in Sentence (1) is located shall be designed to prevent airflow from the feed room to any other part of the floor area of the farm building.
(3)
Enclosed horizontal silos shall be ventilated by
(a)
openings at roof or eave level with an area not less than 1% of the floor area of the silo that consist of
(i)
a continuous ridge opening,
(ii)
openings in both gable ends, or
(iii)
openings in the eaves on each side of the roof, and
(b)
openings at floor level with an area not less than 1% of the floor area of the silo. (See Note A-2.4.2.4.(3)(b)) (See Note A-2.4.2.4.(3))